Fire Behavior
Throughout this series of fires, the fire behavior was very difficult to predict, particularly for wildland fire fighters who were unfamiliar with the fuel conditions and shifting coastal winds encountered in Florida. The mathematical models that are used to predict fire behavior had to be adjusted to account for the very different characteristics of the fuel and its ability to burn in a relatively moist environment.
Fires in thick underbrush fuel are usually very difficult to overhaul, however, the wood fires that normally occur in Florida can usually be fully contained by knocking down the flames with water and then cutting a fire break around them with a plow attached to a tractor. The underbrush would often continue to smolder for several days, however, the fire would be contained within the perimeter. Due to the low humidity and fuel moisture content in 1998, the tangled underbrush material would often continue to burn and eventually reignite the trees and brush, allowing the fire to jump over the firebreak. It was almost impossible to fully extinguish these fires without a soaking rain.
Wildland fires usually tend to diminish at night and begin to regain their energy with the morning sun, reaching a peak curing the afternoon. In Florida, under normal conditions, most fires are reduced to smoldering at night and can often be overhauled in the morning. As the temperatures increased and fuel moisture content decreased during June, the fires became energized earlier in the day and burned later into the evenings. In early July, as the situation reached its peak, some of the fires continued to blaze through the night.
In the coastal areas the winds shifted frequently and often pushed the fires in different directions during different period of the day. A dry wind would push a fire rapidly in one direction for part of the day, then a moist offshore breeze would slow its pace and reverse its direction. Some of the fires burned back and forth for days, slowly expanding within the same general area. Several fires joined together, while others branched out in different directions to form multiple heads.
Major flare-ups occurred during periods of extremely hot and dry weather, particularly with a strong wind from the west. During these periods huge flame fronts were created and ignitions from embers were reported more than one half mile downwind. Under these conditions the fires easily jumped across natural fire breaks, including Interstate 95, and could have crossed the Intracoastal Waterway. The almost flat terrain had very little impact on fire spread, but also provided very few natural fire breaks.
The situation was recognized as being beyond the capability of fire suppression forces, as long as the dry weather continued. It was a matter of time, whether the rain would come before the fires could reach and overwhelm populated areas. Each day the fire fighters hoped for rain that did not come and the situation became more critical.
Fatigue
The fire fighters of Florida fought a war of attrition that went on for almost two months. Fatigue became a major factor, as units were often committed to fighting fires for 14 to 16 hours without sleep before returning for another full day of operations. In some cases they slept in their vehicles and resumed operations at dawn.
During campaign operations, wildland fire crews are usually committed to one fire at a time and normally operate on rotating shifts. A crew might operate for 12 hours, then shutdown for the night while a second shift relieved them. This type of work cycle was virtually impossible to accomplish for the DOF crews and local fire fighters for more than a month.
The local fire departments often had to contend with multiple fires and also had to maintain their 24 hour capability to respond to any other emergency incidents that occurred in their jurisdictions. In many cases, after a full day of fighting fires, they were called out again during the night for new ignitions or rekindles of old fires, as well as for medical and rescue incidents. Many of the volunteers temporarily gave-up their regular employment and became full time fire fighters until the situation was controlled.
It was not unusual for units to travel 40 or 50 miles to work on one fire, then to be directed to turn around and respond back to the area where they had started for another fire. When they could shut down operations for the day, they still had to return to their stations to service their apparatus and equipment. On busy days some of the off-road vehicles logged 150 to 200 miles on the highway.
Command officers and staff support personnel were often on virtually continuous duty, napping for an hour or two when there was opportunity. At command posts and emergency operation centers the planning and logistics functions were active all day and most of the night. The daily decommitment of resources often overlapped with planning and preparation for the next day’s operations.
As the events reached their most critical stage, most of the fire fighters were already exhausted, supplies were running low and their apparatus and equipment needed maintenance in spite of the fatigue factor, many units continued to operate for several days, working all day and all night, trying to hold the fires at the edge of built-up areas or conducting a house to house battle. The most important function for many of the out-of-state personnel, when they arrived, was to relieve the exhausted crews that had been on the front line for weeks. In several cases crews from far away jurisdictions were assigned to staff fire stations, while all of the regularly assigned personnel got their first good rest in more than a month.
Infrared and Satellite Imagery
During the weeks that Florida was experiencing this devastating series of fires, the use of infrared (IR) imagery proved to be very valuable. While a blanket of smoke covered hundreds of square miles, IR images allowed planners to map the locations, extent and progress of fires to see if they were growing and to determine how quickly they were moving and in which directions. The IR scans also provided a very quick and accurate capability to detect new ignitions in remote areas.
The initial use of IR technology was from aircraft flying over the area to survey the fires. Engineers at Kennedy Space Center at Cape Canaveral, which is in close proximity to the fires, observed that the fires were visible on satellite IR images and made this technology available to support the fire fighting operations. The satellite images allowed for the entire area to be scanned on a single pass and for the resulting images to be immediately available via the Internet. The satellite IR images provide very high resolution capability and are fully compatible with digital mapping systems and Global Positioning System (GPS) technology.
The increasing use of GPS to map wildland fires has become very valuable for planning and directing operations and greatly increased the efficiency of aircraft operations. Aircraft can be guided to very precise locations by land based units equipped with handheld GPS units. The same technology can be used to direct ground units to the locations of fires detected by aerial observation or IR scans from aircraft or satellites. The maps can also be transmitted electronically to different locations, including field units with mobile data terminals.
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